R(-)-扁桃酸脱氢酶产生菌的筛选

Screening of the Strain Producing Mandelic Acid Dehydrogenase

选用酵母、乳酸菌、粪链球菌、假丝酵母等 4个种属 18种菌株 ,研究其对苯乙酮酸和苯乙酮酸甲酯的不对称还原催化特性。筛选出一株酵母sp .strainby1,对两种底物皆具有较高的转化活性和光学选择性。底物浓度为 10mmol L ,微生物转化 72h后 ,扁桃酸的得率 80 .83% ,对映体过量值e .e .达 95 .5 % ;微生物转化 2 8h后 ,扁桃酸甲酯的得率 92 .11% ,e .e .值达 91.1%。

Asymmetry reduction of phenyl glyoxylic acid and phenyl glyoxylic methyl ester by Saccharomyces Cerevisiae, Lactoballius, Streptococcus faecalis and Candida albicans was investigated. The Saccharomyces Cerevisiae special strain by1 was selected, which showed higher bioreduction activity and opticselectivity for both substrates. When the concentration of either substrate was 10mmol/L, the yield and enantiomeric excess were 80.83% and 95.5% for mandelic acid after 72h fermentation, and 92.11% and 91.1% for mandelic formate after 28h fermentation.